Railway-traffic-controlling apparatus



C. H. LAY.

RAILWAY TRAFFIC CONTROLLING APPARATUS.

APPLICATION FILED Iu IIs 7, 1920.

1,356,553. Patented Oct. 26,1920.

INVENTOR M ATTORNEY UNITED STATES PATENT OFFICE. j

CHARLES H. LAY, OF PITTSBURGH, PENNSYLVANIA, vASSIGrNOR To THE UNION 'SWITCH & SIGNAL COMPANY, OLE SWISSVALE, PENNSYLVANIA, A CORPO- RATION OF PENNSYLVANIA.

RAILWAY-TEA]?FIG-CONTROLLING APPARATUS.

Specification of Letters Patent.

Patented Oct. 26,1920.

Application filed June 7, 1920. Serial No. 386,986.

T 0 all whom it may concern: 7

Be it known that I, CHARLES H. LAY, a citizen of the United States, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Railway Trafiic Controlling Apparatus, of which the following is a specification.

My invention relates to railway trafiic controlling apparatus and particularly to signaling apparatus for stretches of single track over which traffic moves in both directions. More specifically the invention relates to systems of this type wherein the track is divided into successive blocks and a signal is provided adjacent each endof each block for governing trafiicinto and through the block, the signals being so controlled that when a train enters a block it places at stop the signal governing entrance into the block in the opposite direction and holds such signal at stop until the train leaves the block, while the signal at theentering end is caused to give a proceed or a permissive indication while the train is in the block to permit a following train to enter the block.

One object of my invention is the provision of novel and improved means for controlling the signals in the manner set forth. I will describe one form of apparatus embodying my invention, and will then point out the novel features thereof in claims. 7

The accompanying drawing is a diagrammatic view showing one form and arrange.- ment of apparatus embodying my invention.

Referring to the drawing, the reference characters 1 and 1 designate the track rails of a single track railway C, over which traffic moves in both directions. The track is divided into a plurality of successive blocks of which only one block A-B is shown in the drawing, the rails of this'block being electrically separated from the rails of'the adjoining blocks by insulated joints 2. The rails of the block A--B. are further divided by insulated j oints 2 into two track sections A-D and DB. p

Each sectionof the/block AB is pro connected across the rails of section AD adjacent the end of the block andthe primary of which is connected with a transmission line 4: which is constantly supplied with alternating current by a generator 5. The track relay for section A-D is designated P and is of the polyphase motor type comprising two stator windings and 66, a rotor 67, and a plurality of rotor-operated contacts 37, 82, 48 and 52. The stator winding 65. ofthisrelay is connected across the rails of track section A-D adjacent the middle of the block, while the stator winding 66 is constantly supplied with alternat ing current from the. secondary of a transformer T,the primary of which is connected 'with the-transmission mains 4:. The track circuit for section D-B is similar in that it comprises a transformer T adjacent the end of the block, and a track relay P one windingof which is'connected with the rails adjacent the middle of the block and the other winding of which is connectedwith the sec: ondary of transformer T. As is well understood, the track relays for block A--B will operate in the following manner: VVhena train movingtoward the .rightenters block The reference character -N designatesa 7 three positionrelay comprising a rotor 13 and two stator windings 11. and 12, together witha series of contact fingers 14,15, 16 and 17-, operatively connected with the rotor. The stator winding 11 is constantly: supplied with alternating current from the secondary of transformer T, while the stator winding 12 is at times supplied with alternating current of one relative polarity or the other as hereinafter set forth. The control of this relay N will be best understood by explaining the operation of the relay as a train passes through the block. When the block is unoccupied, relay N is denergized owing to the fact that stator winding 12 is not supplied with current; the contact fingers of the relay then occupy their intermediate or vertical positions as shown in the drawing.

When a train moving toward the left enters block AB it opens track relay P thereby closing a pick-up circuit for winding 12 of relay N, which circuit passes from the right hand terminal of the secondary of transformer T, through wires 26, 27 and 34, contact 14-19, of relay N, wire 36, front point of contact 87 of track relay P wires 12 and 57, winding 12 of relay N, wires 58 and 43, back point of contact 80 of track relay P wire 59, contact 28-16 of relay N, and wires 60, 61 and 68 to the left hand terminal of the secondary of transformer T. It will be observed that when the circuit is traced in this manner the current passes downwardly through winding 12 of relay N. Current of this relative polarity coiiperates with the current in winding 11 in such manner as to cause the contact fingers of relay N to swing to the right. This does not cause contacts 1 119 and 1623 to open, however, because of the length of the'segments 1'9 and 23 forming parts of these contacts, and so the pick-up circuit just traced remains closed. As the front end of the train enters track section A-D, it causes track relay P to open, and this operation of relay P of course, occurs before track relay P closes. The opening of relay P closes a holding circuit for relay N, which circuit passes from the right hand terminal of the secondary of transformer T, through wires 26, 27 and 28, contact 1725, wires 41 and 57, winding 12, wires 58, 43 and 31, back point of contact 32 of track relay P wire 63, contact 21-15 and wires 61 and 68 to the left hand terminal of secondary of transformer T. It will be observed that the current in this circuit is of the same relative polalrity as the current in the first or pick-up circuit for relay N, so that relay Ncontinues to be energized in such direction that its contact fingers are swung to the right until the rear end of the train passes out of block AB. In other words, the second or holding circuit for winding 12 of relay N is not controlled by track relay P I will now assume that a train moving toward the right passes through block A-B. When this train enters the block it immediately opens track relay P thereby closing the following pick-up circuit for winding 12 of relay N: from'the right hand terminal of the secondary of transformer T, through wires 26, 27 and 28, contact 17-21%, wire 29, front point of contact 30 of track relay P wires 48 and 58, winding 12, wires 57 and 12, back point of contact 37 of track relay P wire 62, contact 20-15, and wires 61 and 68, to the left hand terminal of the secondary of transformer T. The relative polarity of this current in winding 12 is opposite Vto the relative polarity of the current in this winding when the first pick-up circuit traced above is closed, and so relay N is now energized in such direction that its contact fingers are swung to the left. When the train passes point D, the consequent opening of track relay P closes a second holding circuit for relay N, which circuit passes from the right hand terminal of the secondary of transformer T, through wires 26, 27 and 84, contact 1418, wires 35 and 58, winding 12, wires 57, 12 and 38, back point-of contact 39 of track relay P wire 6 1, contact 22--16, and wires 60, 61 and 68 to the left hand terminal of the secondary of transformer T. The relative polarity of this current in winding 12 is the same as the relative polarity of the current supplied to the said winding when the second pick up circuit is closed, and so it follows that relay N continues to be energized in such 1 direction that its contacts are swung to'the left until the rear end of the train passes out of block A-B.

It will be seen from the foregoing that when a train moving toward the left enters block AB,'relay N is energized in one direction and continues to be energized in such direction until'the train leaves the block, whereas when a train moving toward the right enters the block this relay is energized in the opposite direction and continues to be so energized until the train leaves the block.

Located adjacent the left hand end of block AB is a roadside signal S which governs traffic into the block from this end. A similar signal S is located adjacent the right hand end of the block for the purpose of governing traffic into the block from the corresponding end. These two signals will hereinafter be termed the end signals, and as here shown, they are in the form of semaphore signals, each indicating stop or proceed according as the semaphore is in the horizontal or an inclined position. The block is further provided with two intermediate signals S and S located in advance of the end signals respectively, and each of which, as here shown, is in the form of a light signal comprising a green lamp G and a red lamp R. In accordance with customary practice, each of these intermediate signals indicates proceed when the green lamp is illuminated, and stop when the red lamp is. illuminated.

The end signal S? is provided with a main through wires 26, 27 and 34, contact 14- -19,

of relay N, wire 36, front point of contact 37 of track relay P wire 38, front point of contact 39 of track relay P wire 40, op

erating mechanism of signal and common wire 0 to the left hand terminal of the secondary of transformer T. It will be seen that in so far as this circuit alone is concerned, signal S will indicate proceed when both track relays are energized, and stop when either of these relays is open. This circuit is provided, however, with a branch around contact l t-19 and contact 37, which branch passes from wire 27, through wire 28, contact 17-25 of relay N, wire 41, and wire 42 to wire 38. It follows, therefore, that when relay N is energized in such direction that its contacts are swung to the right, and track relay P is energized, signal S will indicate proceed. Signal S is similarly provided with a main circuit which passes from the right hand terminal of the secondary of transformer T, through wires 26, 27 and 28, contact 17-24L, of relay N, wire 29, front point of contact 30 of track relay P wire 31, front point of contact 32 of relay P wire 33, operating mechanism of signal S and common wire 0 .to the left hand terminal of the secondary of transformer T. In .so far as this circuit is concerned signal S will indicate stop when either track relay P or P is open. This circuit is provided with a branch around contact 17'24iof relay N and contact 30 of track relay P however, which branch passes from wire 27, through wire 34, contact 1418 of relay N, and wires 35 and4c3 to wire 31. It follows, therefore, that when track relay P is open and track relay P closed, signal S will indicate proceed, provided that the three-position relay N is energized in such direction that its contact fingers are swung to the left.

Considering now the intermediate signals S and S the green or proceed lamp G of signal S is provided with a circuit which passes from the right hand terminal of the secondary transformer T, through wires 26,

4L4: and 51, back contact 52 of track relay P wire 53, front'point of contact 5430f track relay P wire 55, lamp G of signal. S and common wire 0 to the left hand terminal of the secondary of transformer T. This circuit is closed only when track relay P is deenergized and track relay P is energized. Thered lamp It of signal S is provided with a circuit which passes from the right hand terminal of the secondary of trans former T, through wires 26, 44L and 51, back contact 52 of track relay P wire 53, back point of contact 54: of track relay P wire 56, lamp R and common wire 0 to the left hand terminal of the secondary of transformer T. This circuit is closed only when both track relays P and P are deenergized. The green lamp G of signal S is provided with a circuit which passes through back contact 46 of track relay P frontfpoint of contact 18 of track relay P and the lamp G, so that this lamp will be illuminated onl when relay P is open and relay P is close The red lamp R for this same signal is provided with a circuit which passes through back' contact 46 of track relay P andback contact: 48 of track relay P which circuit will, therefore, be closed only when both track relays are deenergized.

The operation of the entire apparatus is as follows: i I

VVhen the block A -B is unoccupied, the partsv of the apparatus occupy the positions in which they are shown in the drawing, so that all signals S and S indicate proceed and the lamps of signals S and S are extinguished. When a train moving toward the left enters the block A-B the opening of track relay P opens the circuit forsignal S at contact 39, so that this signal moves to the stop position. The opening of track relay P also opens at contact 30 the circuit for signal S, so that this signal likewise moves to the stop position. This operation of track relay P closes atcontact 46 the circuit for the green lamp G of signal S, so that this lamp becomes illuminated, and the same operation opens at contact 54 the'circuit for the. green lamp G of signal S, so that the latter signal is prevented from giving a proceed indication. 1 Furthermore, the opening of track. relay P closes at the back point of contact 30 the first pick-up circuit for relay N, so that this re lay becomes energized in such direction that its contact fingers are swung to theright. As the front end of the train enters section A'D, track relay P opens, thereby closing at .the back. point of contact'32 thefirst holding circuit for relay N, so that this relay remains energized during the passage of the train through the remainder of the block. The reversal of contact 48 of track relay P eXtinguishes the green lamp G of signal S? and illuminates the rad lamp R of this signal, passes out of section DB, track relay P becomes energized, thereby extinguishing the red lamp R of the intermediate signal S. The closing of the front point of contact'39 of track relay P closes the circuit for end signal S through contact 1725 of relay N, so that signals returns to the pr'bceed position, thereby permitting a following train moving toward theleft to enter block A-B. Signal S remains at stop,

however, as long. as any part of the train occupies :the block, becausethe circuit for this signal is opened at the front point of contact 32 of track relay P When the rear 115 As the rear end of, the train I r end of the train passes out of track section A-D, track relay P closes, thereby opening the holding circuit for relay N, so that this relay returns to its denergized condition. Signal S then returns to its proceed position, so that all parts of the apparatus are again in the positions in which they are shown in the drawing.v

.The operation of the apparatus during the passage of a train through the block from left to right will be understood fromthe foregoing without further explanation.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope ofthe appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a block of railway track over which traffic moves in both directions, two track relays for said block arranged to be operated successively by a train passing through the block, the relay first operated remaining in operated condition until the other relay has been operated, a three position relay comprising a constantly energized winding and a second winding, the relay being responsive to reversals of the relative polarity ofthe current supplied to said second winding, means controlled by said track relays for supplying current of one relative polarity or the other to said second winding according as one track relay or the other is first operated by a train entering the block and for maintaining the supply of current of the initial polarity to said winding until the train leaves the block, and signals for said block controlled by said three position relay.

2. In combination, a block of railway track over which. traiiic moves in both directions, two track relays for said block arranged to be operated successively by a train passing through the block, the relay first operated remaining in operated condition until the other relay has been operated, a three position relay comprising a constantly energized winding and a second winding, the relay being responsive to reversals of the rela tive polarity of the current supplied to said second winding, a pick-up circuit for said second winding for supplying current of one relative polarity thereto and including a front contact of one track relay and a back contact of the other track relay, a holding circuit for said second winding including a back contact of the second track relay and a contact of the three position relay which is closed when the latter relay is energized by said pick-up circuit, said holding circuit supplying current to said winding of the same relative polarity as said pick-up circuit, a second pick-up circuit for said seccluding a back contact of the first track re- 1 lay and a front contact of the other track re-' lay, a second holding circuit for said second winding for supplying current of the said opposite polarity thereto and including a back contact of the first track relay and a contact of the three position relay which is closed when the latter is energized by the second pick-up circuit, and signals for said block controlled by said three position relay.

3. In combination, a block of railway track over which traiiic moves in both directions, a three-position relay comprising a winding constantly supplied with current and a second winding, means controlled by a train entering said block for supplying current of one relative polarity or the other to said second winding according as said train moves in one direction or the other and for continuing the supply of current of the said polarity to such -winding until the train leaves the block and signals for the block controlled by said three-position relay.

4:. In combination, a block of railway track over which trafiic moves in both directions, two track relays for said block arranged to be operated successively by a train passing through the block, the relay first op? erated remaining in operated condition until the other relay has been operated, a threeposition relay comprising a constantly energized winding and a second winding, the relay being responsive to reversals of the relative polarity of the current supplied to the second winding; a pick-up circuit for said second winding for supplying current of one relative polarity thereto to move the contacts of the relay to one extreme position, said circuit including a front contact of one track relay, a back contact of the other track relay and a contact of the three-position re lay which is closed from the neutral'position to said extreme position of the contacts; a holding circuit for said second winding including a back contact of the second track relay, and a contact of the three-position relay closed when the latter is energized by said pick-up circuit, said holding circuit supplying current to said winding of the same relative polarity as said pick-up circuit; a second pick-up circuit for said second winding for supplying current of the opposite relative polarity thereto to move the contacts of the three position relay to the other extreme position, said circuit including a back contact of the first track relay, a front contact of the other track relay, and a contact of the three-position relay which is closed from neutral to the last-mentioned position; a second holding circuit for said second winding for supplying current of the said opposite polarity thereto and including a back contact of the first track relay and a contact of the three-position relay which is closed when the latter is energized by the second pick-up circuit, and signals for said block controlled by said threeposition relay In testimony whereof I afiix my signature in presence of two witnesses.

CHARLES H. LAY. Witnesses A. HERMAN WEGNER, J. H. STULL. 

